JP2022032011A - Vibration device - Google Patents

Abstract

To provide a vibration device that can be reduced in size in plan view.SOLUTION: A vibration device 1 comprises: a stationary part 50 that projects from a substrate 3 in a Z direction; a base 40 that is connected with the stationary part 50; and a first vibration arm 11 and a second vibration arm 21 that extend from the base 40 in a Y direction and are arranged side by side in the Z direction. The stationary part 50 is included in the contour of the base 40 in plan view from the Z direction and has a smaller area than that of the base 40.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vibrating device.

Conventionally, as shown in Patent Document 1, a fixed portion protruding from a substrate, a base extending with a gap between the fixed portion and the substrate, and a base extending from one end of the base as a pair. An oscillator having a vibrating arm and a pair of vibrating arms having vibrating pieces overlapping each other in a plan view is known.

Japanese Unexamined Patent Publication No. 2015-466807

However, the vibrating piece described in Patent Document 1 has a structure in which a part of the fixed portion protrudes from the base in a plan view because a gap is provided between the substrate and the base of the vibrating piece. There is a problem that it is difficult to reduce the size.

The vibrating device includes a substrate having a flat surface, a fixed portion protruding from the substrate in the normal direction of the plane, a base connected to the fixed portion, and a direction intersecting the normal direction from the base portion. A plurality of vibrating arms extending and arranged side by side in the normal direction are provided, and the fixed portion is included in the outer shape of the base in a plan view from the normal direction, and the base portion is included. Area is smaller than.

The plan view which shows the schematic structure of the vibration device which concerns on Embodiment 1. FIG. FIG. 2 is a cross-sectional view taken along the line AA in FIG. The flowchart which shows the main manufacturing process of the vibration device which concerns on Embodiment 1. FIG. 6 is a schematic cross-sectional view showing a manufacturing process of the vibration device according to the first embodiment. FIG. 6 is a schematic cross-sectional view showing a manufacturing process of the vibration device according to the first embodiment. FIG. 6 is a schematic cross-sectional view showing a manufacturing process of the vibration device according to the first embodiment. FIG. 6 is a schematic cross-sectional view showing a manufacturing process of the vibration device according to the first embodiment. FIG. 6 is a schematic cross-sectional view showing a manufacturing process of the vibration device according to the first embodiment. The plan view which shows the schematic structure of the vibration device which concerns on Embodiment 2. FIG. 9 is a cross-sectional view taken along the line BB in FIG. The plan view which shows the schematic structure of the vibration device which concerns on Embodiment 3. FIG. 11 is a cross-sectional view taken along the line CC in FIG. The plan view which shows the schematic structure of the vibration device which concerns on Embodiment 4. FIG. 6 is a cross-sectional view taken along the line DD in FIG. The plan view which shows the schematic structure of the vibration device which concerns on Embodiment 5. FIG. 15 is a cross-sectional view taken along the line EE in FIG. FIG. 15 is a cross-sectional view taken along the line FF in FIG. The plan view which shows the schematic structure of the vibration device which concerns on Embodiment 6. FIG. 8 is a cross-sectional view taken along the line GG in FIG. FIG. 8 is a cross-sectional view taken along the line OH in FIG.

1. 1. Embodiment 1
The vibration device 1 according to the first embodiment will be described with reference to FIGS. 1 and 2. Note that FIG. 1 illustrates a state in which the lid 4 is removed for convenience of explaining the internal configuration of the vibration device 1. Further, in the figure, wiring, terminals, and the like are omitted for convenience of explanation, and the dimensional ratio of each component is different from the actual one.

In the coordinates added to the drawings, the three axes orthogonal to each other will be described as the X-axis, the Y-axis, and the Z-axis. The direction along the X axis is the "X direction", the direction along the Y axis is the "Y direction", the direction along the Z axis is the "Z direction", and the direction of the arrow is the plus direction. Further, the positive direction in the Z direction will be described as "up" or "upward", and the negative direction in the Z direction will be described as "down" or "downward". Further, in a plan view when viewed from the Z direction, the surface on the plus side in the Z direction will be described as the upper surface, and the surface on the minus side in the Z direction opposite to this will be described as the lower surface.

As shown in FIGS. 1 and 2, the vibration device 1 includes a vibration element 2, a substrate 3, and a lid 4. The substrate 3 has a flat plate shape, and the substrate 3 has a flat upper surface 3h. The vibrating element 2 is fixed to the upper surface 3h of the substrate 3 via a fixing portion 50 described later. The lid 4 has a box shape having a recess that serves as an accommodation space 6 for accommodating the vibrating element 2 in the central portion of the lower surface on the side where the lid 4 and the substrate 3 are connected so as to cover the vibrating element 2. It is fixed to the upper surface 3h of the substrate 3.

The vibrating element 2 includes a first vibrating element 10 and a second vibrating element 20. The second vibrating element 20 is arranged on the positive side in the Z direction of the first vibrating element 10, and the first vibrating element 10 and the second vibrating element 20 are Z in the normal direction of the upper surface 3h of the substrate 3. They overlap in a plan view from the direction.

The first vibrating element 10 includes a first base 41, a first vibrating arm 11 extending from the first base 41, and a first driving unit 12 and a second driving unit 13 for vibrating the first vibrating arm 11. It has a fixing portion 50 for fixing the vibrating element 2 to the substrate 3 so as to project from the lower surface of the first base portion 41 to the minus side in the Z direction.

The second vibrating element 20 includes a second base portion 42, a second vibrating arm 21 extending from the second base portion 42, and a third driving unit 22 and a fourth driving unit 23 for vibrating the second vibrating arm 21. , Have. The thickness of the second base 42 in the Z direction is formed to be thicker than the thickness of the second vibrating arm 21 in the Z direction so that the lower surface of the second base 42 is located below the lower surface of the second vibrating arm 21. Has been done.

The upper surface of the first base 41 and the lower surface of the second base 42 are connected so as to overlap each other in a plan view, whereby a base 40 having the first base 41 and the second base 42 is formed. ing.

The first vibrating arm 11 and the second vibrating arm 21 extend from one end 40a on the positive side in the Y direction of the base 40 in the Y direction intersecting the Z direction which is the normal direction of the upper surface 3h of the substrate 3. .. Further, the first vibrating arm 11 and the second vibrating arm 21 are arranged side by side in the Z direction and overlap each other in a plan view. As described above, by overlapping the plurality of vibrating arms of the first vibrating arm 11 and the second vibrating arm 21 in a plan view, it is possible to obtain a miniaturized vibrating device 1 in the plane direction of the substrate 3. ..

On the lower surface of the first vibrating arm 11, a first driving unit 12 in which the second electrode 17, the piezoelectric film 16, and the first electrode 15 are laminated in this order from the first vibrating arm 11 side is provided. On the upper surface of the first vibrating arm 11, a second driving unit 13 in which the first electrode 15, the piezoelectric film 16, and the second electrode 17 are laminated in this order from the first vibrating arm 11 side is provided.

On the lower surface of the second vibrating arm 21, a third driving unit 22 is provided in which the first electrode 15, the piezoelectric film 16, and the second electrode 17 are laminated in this order from the second vibrating arm 21 side. On the upper surface of the second vibrating arm 21, a fourth drive unit 23 is provided in which the second electrode 17, the piezoelectric film 16, and the first electrode 15 are laminated in this order from the side of the second vibrating arm 21.

The first electrodes 15 of the first drive unit 12, the second drive unit 13, the third drive unit 22, and the fourth drive unit 23 are electrically connected by wiring (not shown). .. Further, the second electrodes 17 of the first drive unit 12, the second drive unit 13, the third drive unit 22, and the fourth drive unit 23 are electrically connected by wiring (not shown). .. Further, the first electrode 15 and the second electrode 17 are electrically connected to a plurality of external electrodes 19 provided on the lower surface of the substrate 3 via through electrodes and interlayer wiring (not shown).

For the first electrode 15 and the second electrode 17, for example, materials such as TiN, ITO, Au, Cu, and Al can be used. For the piezoelectric film 16, for example, materials such as AlN, ZnO, and PZT can be used. Further, in addition to the first electrode 15, the piezoelectric film 16, and the second electrode 17, a temperature correction film for preventing a decrease in the resonance frequency due to a change in temperature, an insulating alignment film for improving the orientation of the piezoelectric film 16, and the like are provided. It may be formed.

The piezoelectric film 16 of the first drive unit 12 and the second drive unit 13 is in the Y direction, which is the extension direction of the first vibrating arm 11, when a voltage is applied between the first electrode 15 and the second electrode 17. It expands and contracts. Since the first drive unit 12 and the second drive unit 13 have the first electrode 15, the piezoelectric film 16 and the second electrode 17 in the reverse stacking order, the piezoelectric film of the first drive unit 12 is used. When 16 is stretched, the piezoelectric film 16 of the second drive unit 13 is shrunk, and conversely, when the piezoelectric film 16 of the first drive unit 12 is shrunk, the piezoelectric film 16 of the second drive unit 13 is stretched. Therefore, since the upper surface and the lower surface of the first vibrating arm 11 expand and contract in the opposite direction, the first vibrating arm 11 can be flexed and vibrated in the Z direction.

Further, the first drive unit 12 and the second drive unit 13 of the first vibration element 10 and the third drive unit 22 and the fourth drive unit 23 of the second vibration element 20 are the first electrode 15 and the piezoelectric film 16. Since the stacking order of the second electrode 17 and the second electrode 17 is reversed, the first vibrating arm 11 of the first vibrating element 10 and the second vibrating arm 21 of the second vibrating element 20 are along the Z direction. And vibrate in opposite phase to each other. That is, in the vibrating element 2, when the tip of the first vibrating arm 11 is displaced to the positive side in the Z direction, the tip of the second vibrating arm 21 is displaced to the negative side in the Z direction, and conversely, the tip of the first vibrating arm 11 is displaced. When the tip portion is displaced to the minus side in the Z direction, the tip portion of the second vibrating arm 21 vibrates due to bending vibration that is displaced to the plus side in the Z direction.

In this way, the first vibrating arm 11 of the first vibrating element 10 and the second vibrating arm 21 of the second vibrating element 20 vibrate in opposite phases, so that the vibration of the vibrating element 2 is stabilized. In the present embodiment, the vibrating element 2 uses two vibrating arms, a first vibrating arm 11 of the first vibrating element 10 and a second vibrating arm 21 of the second vibrating element 20. Three or more vibrating arms may be arranged side by side in the Z direction. When three or more vibrating arms are arranged side by side in the Z direction, it is preferable that the vibrations of the adjacent vibrating arms are driven so as to be in opposite phase to each other.

Further, in the present embodiment, the first drive unit 12, the second drive unit 13, the third drive unit 22, and the fourth drive unit 23 are provided on the lower surface and the upper surface of the first vibrating arm 11 and the second vibrating arm 21, respectively. However, the drive unit may be provided only on one surface of the lower surface or the upper surface of the vibrating arm. For example, the same vibration as in the present embodiment can be caused by only two of the first drive unit 12 and the third drive unit 22, or only two of the second drive unit 13 and the fourth drive unit 23.

Further, in the present embodiment, the drive unit is provided on both the first vibrating arm 11 and the second vibrating arm 21, but it is driven by either the first vibrating arm 11 or the second vibrating arm 21. It is also possible to provide a portion and not to provide a drive portion on the other vibrating arm. For example, two of the first drive unit 12 and the second drive unit 13, two of the third drive unit 22 and the fourth drive unit 23, or the first drive unit 12, the second drive unit 13, Only one of the third drive unit 22 and the fourth drive unit 23 may be used. By substantially matching the natural frequency of the first vibrating arm 11 and the natural frequency of the second vibrating arm 21, when one vibrating arm provided with a drive unit flexes and vibrates, the other without a drive unit. Since the vibrating arm of No. 1 bends and vibrates in the opposite phase due to the resonance action, it is possible to vibrate in the same manner as in the present embodiment by providing a drive unit on at least one vibrating arm.

The fixing portion 50 fixes the vibrating element 2 to the upper surface 3h of the substrate 3. The lower surface of the fixing portion 50 is connected to the upper surface 3h of the substrate 3, and the upper surface of the fixing portion 50 is connected to the lower surface of the base portion 40. In other words, the fixing portion 50 projects from the substrate 3 to the plus side in the Z direction, which is the normal direction of the upper surface 3h of the substrate 3.

In the present embodiment, the fixing portion 50 is a substantially rectangular parallelepiped, and the area S1 of the substrate side connecting portion 50r in which the lower surface of the fixing portion 50 is connected to the upper surface 3h of the substrate 3 in a plan view seen from the Z direction. The area S2 of the base side connecting portion 50h in which the upper surface of the fixing portion 50 is connected to the lower surface of the base portion 40 is substantially equal to.

The fixed portion 50 is included in the outer shape of the base 40 in a plan view seen from the Z direction, which is the normal direction of the upper surface 3h of the substrate 3, and the area of the fixed portion 50 is smaller than the area of the base 40. .. Since the fixed portion 50 is included in the outer shape of the base 40 in a plan view, the fixed portion 50 does not protrude from the base 40 in a plan view, so that the vibration is reduced in the plane direction of the substrate 3. Device 1 can be obtained. Further, since the area of the fixed portion 50 is smaller than the area of the base 40 in a plan view, it becomes difficult for the vibration energy of the vibrating element 2 to be transmitted from the base 40 to the fixed portion 50, and the vibration energy of the vibrating element 2 leaks to the substrate 3. Since it is possible to suppress the vibration device 1, it is possible to obtain a vibration device 1 having high vibration efficiency.

Further, the fixed portion 50 is a side opposite to one end 40a on the plus side in the Y direction, which is the side on which the first vibrating arm 11 and the second vibrating arm 21 of the base 40 extend, in a plan view seen from the Z direction. It is unevenly arranged on the minus side in the Y direction. In the present embodiment, the fixing portion 50 is arranged so that the center line L1 in the Y direction of the fixing portion 50 is located on the minus side in the Y direction with respect to the center line L2 in the Y direction of the base portion 40. By arranging the fixed portion 50 biased to the side opposite to the extending side of the first vibrating arm 11 and the second vibrating arm 21 of the base 40 in a plan view, the first vibrating arm 11 and the second vibrating arm 21 are arranged. Since the distance between the 21 and the fixing portion 50 can be separated, it is possible to prevent the vibration energy of the vibrating element 2 from leaking to the substrate 3.

Further, in the present embodiment, the upper surface of the second vibrating arm 21 and the upper surface of the base 40 are on the same plane, but the upper surface of the base 40 is located above the upper surface of the second vibrating arm 21. The upper surface of the base 40 may be projected to the plus side in the Z direction. By projecting the upper surface of the base 40 upward, the weight of the base 40 is increased, the vibration element 2 is stabilized, and the leakage of vibration energy can be reduced.

Next, a method of manufacturing the vibration device 1 will be described with reference to FIGS. 3 to 8. As shown in FIG. 3, the manufacturing method of the vibrating device 1 includes a first vibrating element forming step, a second vibrating element forming step, a substrate connecting step of connecting the first vibrating element 10 to the substrate 3, and a first vibration. It includes a vibration element forming step of connecting the element 10 and the second vibration element 20 to form the vibration element 2, and a lid connection step of connecting the lid 4 to the substrate 3.

1.1 First vibrating element forming step As shown in FIG. 4, the first vibrating element 10 is formed in step S101. Specifically, a silicon wafer is etched to form a first vibrating arm 11, a first base portion 41, and a fixing portion 50.
Next, by a photolithography technique, the first drive unit 12 and the second drive unit 13 including the first electrode 15, the piezoelectric film 16, and the second electrode 17 are placed on the lower surface and the upper surface of the first vibrating arm 11. Form each.

1.2 Second vibrating element forming step As shown in FIG. 5, the second vibrating element 20 is formed in step S102. Specifically, the silicon wafer is etched to form the second vibrating arm 21 and the second base portion 42.
Next, by a photolithography technique, the third drive unit 22 and the fourth drive unit 23 including the first electrode 15, the piezoelectric film 16, and the second electrode 17 are placed on the lower surface and the upper surface of the second vibrating arm 21. Form each.

1.3 Board connection process As shown in FIG. 6, in step S103, the first vibrating element 10 is connected to the board 3. Specifically, first, the substrate 3 is prepared. The substrate 3 is a rectangular flat plate formed by etching a silicon wafer, which is larger than the first vibrating element 10 and the second vibrating element 20 in a plan view. The substrate 3 has an external electrode 19 formed by a photolithography technique, a through electrode (not shown), and wiring.
Next, the lower surface of the fixed portion 50 of the first vibrating element 10 and the upper surface 3h of the substrate 3 are connected. As the connection method, for example, direct bonding, anode bonding, diffusion bonding, metal eutectic bonding and the like can be used. In the present embodiment, the substrate 3 is made of silicon, but may be made of insulating ceramics, glass, or the like.

1.4 Vibration element forming process As shown in FIG. 7, in step S104, the first vibration element 10 and the second vibration element 20 are connected to form the vibration element 2. Specifically, the upper surface of the first base 41 of the first vibrating element 10 and the second vibrating element 20 so that the first vibrating element 10 and the second vibrating element 20 overlap each other in a plan view. The lower surface of the base 42 is connected to the lower surface. As a result, the vibrating element 2 to which the first vibrating element 10 and the second vibrating element 20 are connected is formed. As the connection method, for example, direct bonding, anode bonding, diffusion bonding, metal eutectic bonding and the like can be used.

1.5 Cover connection step As shown in FIG. 8, in step S105, the substrate 3 and the lid 4 are connected. Specifically, first, the lid 4 is prepared. The lid 4 has a box shape having a recess larger than that of the vibrating element 2 formed by etching a silicon wafer in the center of the lower surface.
Next, the upper surface 3h of the substrate 3 and the lower surface of the lid 4 are connected. As the connection method, for example, direct bonding, anode bonding, diffusion bonding, metal eutectic bonding and the like can be used. In this way, the recess of the lid 4 surrounds the vibrating element 2, so that the vibrating device 1 having the accommodating space 6 accommodating the vibrating element 2 can be obtained. In the present embodiment, the lid 4 is made of silicon, but may be made of metal, ceramics, glass, or the like.

The first vibrating element 10, the second vibrating element 20, the substrate 3, and the lid 4 may be separated from the wafer on which they are formed by dicing and then connected, or they may be separated. Even if a wafer in which a plurality of first vibrating elements 10, a second vibrating element 20, a substrate 3, and a lid 4 are formed is connected by a batch processing method without using a batch processing method, the wafers are individually diced. I do not care.

In the present embodiment, the substrate 3, the fixing portion 50, the base portion 40, the first vibrating arm 11, the second vibrating arm 21, and the lid 4 are manufactured using silicon. By using a semiconductor material such as polysilicon or amorphous silicon, it can be easily processed into a desired shape.

The manufacturing method of the vibrating device 1 is not limited to the manufacturing method described above, and for example, a semiconductor material such as polysilicon or amorphous silicon is formed on a wafer on which the first vibrating element 10 is formed by using a CVD method, a sputtering method, or the like. The second vibrating element 20 may be formed in a laminated structure above the first vibrating element 10 by a semiconductor process in which a film is formed and patterning is repeated using a photolithographic technique or the like.

As described above, according to the present embodiment, the following effects can be obtained. The first vibrating arm 11 extending from the base 40 and the second vibrating arm 21 are arranged side by side in the Z direction and overlap each other in a plan view. Further, the fixed portion 50 is a base 40 in a plan view. By being included in the outer shape of the substrate 3, it is possible to obtain a miniaturized vibration device 1 in the plane direction of the substrate 3. Further, since the area of the fixed portion 50 is smaller than the area of the base portion 40 in a plan view, the leakage of the vibration energy of the vibration element 2 can be suppressed, and the vibration device 1 having high vibration efficiency can be obtained.

2. 2. Embodiment 2
Next, the vibration device 1a according to the second embodiment will be described with reference to FIGS. 9 and 10. In the following description, the differences from the above-described first embodiment will be mainly described, and the same components as those in the first embodiment are designated by the same reference numerals and duplicated description will be omitted.

The vibration device 1a according to the present embodiment has a different shape of the vibration element 2a from the vibration device 1 of the first embodiment. Specifically, the shape of the fixed portion 50a of the first vibrating element 10a is different, and the fixed portion 50a has a constricted portion 55.

As shown in FIGS. 9 and 10, the fixing portion 50a is placed between the substrate side connecting portion 50r of the fixing portion 50a and the base side connecting portion 50h of the fixing portion 50a, and the upper surface 3h of the substrate 3 of the fixing portion 50a. The cross-sectional area of the cross section parallel to the above has a constricted portion 55 that changes from decreasing to increasing toward the plus side in the Z direction, which is the direction from the substrate side connecting portion 50r to the base side connecting portion 50h.

As shown in FIG. 9, in a plan view, the area S3 of the constricted portion 55 of the fixed portion 50a is smaller than the area S1 of the substrate-side connecting portion 50r of the fixed portion 50a. Further, in a plan view, the area S3 of the constricted portion 55 of the fixed portion 50a is smaller than the area S2 of the base side connecting portion 50h of the fixed portion 50a. In the present embodiment, the area S1 of the substrate side connection portion 50r and the area S2 of the base side connection portion 50h are substantially the same, but the area S1 of the substrate side connection portion 50r and the area S2 of the base side connection portion 50h. And may be different.

As shown in FIG. 10, the fixed portion 50a has a drum shape having a constricted portion 55 in a cross-sectional view in the X direction. The cross-sectional area of the cross section of the fixed portion 50a parallel to the upper surface 3h of the substrate 3 gradually decreases from the substrate side connecting portion 50r of the fixed portion 50a toward the constricted portion 55, and from the constricted portion 55 to the base portion of the fixed portion 50a. It gradually increases toward the side connection portion 50h. In the present embodiment, the cross-sectional area of the fixed portion 50a parallel to the upper surface 3h of the substrate 3 changes continuously. For example, the fixed portion 50a is stepped and the fixed portion is fixed. The cross-sectional area of 50a may be changed discontinuously. However, if the cross-sectional area of the fixed portion 50a is discontinuously changed, when stress is applied to the fixed portion 50a from the outside, the stress is concentrated on the portion where the cross-sectional area of the fixed portion 50a changes discontinuously. Since the fixed portion 50a may be damaged, it is preferable to continuously change the cross-sectional area of the fixed portion 50a.

According to the present embodiment, the following effects can be obtained in addition to the effects in the first embodiment.
By providing the constricted portion 55 in the fixed portion 50a, the vibration energy of the vibrating element 2a is less likely to be transmitted from the fixed portion 50a to the substrate 3, and the leakage of the vibration energy of the vibrating element 2a can be further suppressed. 1a can be obtained. Further, since it is possible to secure a wide area for each of the board-side connecting portion 50r in which the fixing portion 50a is connected to the substrate 3 and the base-side connecting portion 50h in which the fixing portion 50a is connected to the base portion 40, the substrate side can be secured. The fixed portion 50a is less likely to be damaged at the connecting portion 50r or the base side connecting portion 50h, and a highly reliable vibration device 1a can be obtained.

3. 3. Embodiment 3
Next, the vibration device 1b according to the third embodiment will be described with reference to FIGS. 11 and 12. In the following description, the differences from the above-described first embodiment will be mainly described, and the same components as those in the first embodiment are designated by the same reference numerals and duplicated description will be omitted.

The vibration device 1b according to the present embodiment has a different shape of the vibration element 2b from the vibration device 1 of the first embodiment. Specifically, the shape of the fixed portion 50b of the first vibrating element 10b is different, and the fixed portion 50b has a quadrangular pyramid trapezoidal shape.

As shown in FIGS. 11 and 12, the fixing portion 50b has a cross-sectional area parallel to the upper surface 3h of the substrate 3 of the fixing portion 50b from the substrate side connecting portion 50r of the fixing portion 50b to the base side connecting portion of the fixing portion 50b. It has a quadrangular pyramid trapezoidal shape that gradually decreases toward 50 hours, and has a tapered shape in a cross-sectional view seen from the X direction.

As shown in FIG. 11, in a plan view, the area S1 of the substrate-side connecting portion 50r of the fixed portion 50b and the area S2 of the base-side connecting portion 50h of the fixed portion 50b are different from each other, and the relationship of S1 ≠ S2 is satisfied. Further, the area S1 of the substrate-side connecting portion 50r of the fixing portion 50b is larger than the area S2 of the base-side connecting portion 50h of the fixing portion 50b, and satisfies the relationship S1> S2.

In the present embodiment, the cross-sectional area of the fixed portion 50b parallel to the upper surface 3h of the substrate 3 is continuous from the substrate side connecting portion 50r of the fixing portion 50b toward the base side connecting portion 50h of the fixing portion 50b. However, for example, the fixed portion 50b may be stepped so that the cross-sectional area of the fixed portion 50b changes discontinuously.

According to the present embodiment, the following effects can be obtained in addition to the effects in the first embodiment.
In a plan view, the area S1 of the substrate side connection portion 50r of the fixed portion 50b and the area S2 of the base side connection portion 50h of the fixed portion 50b satisfy the relationship S1 ≠ S2, so that the vibration device 1b with high vibration efficiency is satisfied. Can be obtained. This is the smaller area side of the substrate side connection portion 50r of the fixing portion 50b or the base side connection portion 50h of the fixing portion 50b, that is, in the present embodiment, at the base side connection portion 50h of the fixing portion 50b, the vibrating element 2b. This is because the vibration energy is less likely to be transmitted from the base 40 to the fixed portion 50b, and the leakage of the vibration energy can be further suppressed.

Further, in a plan view, the area S1 of the substrate side connection portion 50r of the fixed portion 50b and the area S2 of the base side connection portion 50h of the fixed portion 50b satisfy the relationship of S1> S2, so that the substrate of the fixed portion 50b is satisfied. Since the area S1 of the side connecting portion 50r can be secured widely, the fixed portion 50b is less likely to be damaged in the substrate side connecting portion 50r, and a highly reliable vibration device 1b can be obtained.

4. Embodiment 4
Next, the vibration device 1c according to the fourth embodiment will be described with reference to FIGS. 13 and 14. In the following description, the differences from the above-described first embodiment will be mainly described, and the same components as those in the first embodiment are designated by the same reference numerals and duplicated description will be omitted.

The vibration device 1c according to the present embodiment has a different shape of the vibration element 2c from the vibration device 1 of the first embodiment. Specifically, the shape of the fixed portion 50c of the first vibrating element 10c is different, and the fixed portion 50c has an inverted square pyramidal trapezoidal shape.

As shown in FIGS. 13 and 14, the fixing portion 50c has a cross-sectional area parallel to the upper surface 3h of the substrate 3 of the fixing portion 50c from the substrate side connecting portion 50r of the fixing portion 50c to the base side connecting portion of the fixing portion 50c. It has an inverted square pyramidal trapezoidal shape that gradually increases toward 50 hours, and has an inverted tapered shape in a cross-sectional view seen from the X direction.

As shown in FIG. 13, in a plan view, the area S1 of the substrate-side connecting portion 50r of the fixed portion 50c and the area S2 of the base-side connecting portion 50h of the fixed portion 50c satisfy the relationship of S1 ≠ S2. Further, the area S1 of the substrate side connecting portion 50r of the fixing portion 50c is smaller than the area S2 of the base side connecting portion 50h of the fixing portion 50c, and the relationship of S1 <S2 is satisfied.

In the present embodiment, the cross-sectional area of the cross section of the fixing portion 50c parallel to the upper surface 3h of the substrate 3 is continuous as it goes from the substrate side connecting portion 50r of the fixing portion 50c toward the base side connecting portion 50h of the fixing portion 50c. However, for example, the fixed portion 50c may be formed in a stepped shape so that the cross-sectional area of the fixed portion 50c changes discontinuously.

According to the present embodiment, the following effects can be obtained in addition to the effects in the first embodiment.
In a plan view, the area S1 of the substrate-side connecting portion 50r of the fixed portion 50c and the area S2 of the base-side connecting portion 50h of the fixed portion 50c satisfy the relationship of S1 ≠ S2, thereby having the same effect as that of the third embodiment. Can be obtained, and a vibration device 1c having high vibration efficiency can be obtained.

Further, in a plan view, the relationship between the area S1 of the substrate-side connecting portion 50r of the fixed portion 50c and the area S2 of the base-side connecting portion 50h of the fixed portion 50c satisfies the relationship of S1 <S2, thereby increasing productivity. A good vibrating device 1c can be obtained. This is because when the wafer is etched to form the fixed portion 50c, the base side connecting portion 50h of the fixed portion 50c can be formed without undercutting, so that the etching time can be shortened and the fixed portion 50c can be easily manufactured. Because it becomes.

5. Embodiment 5
Next, the vibration device 1d according to the fifth embodiment will be described with reference to FIGS. 15 to 17. In the following description, the differences from the above-described first embodiment will be mainly described, and the same components as those in the first embodiment are designated by the same reference numerals and duplicated description will be omitted.

The vibration device 1d according to the present embodiment has a different vibration direction of the vibration element 2d than the vibration device 1 of the first embodiment. Specifically, the vibrating element 2d includes a first vibrating element 10d, a second vibrating element 20d, and a third vibrating element 30, a first vibrating element 10d, a second vibrating element 20d, and a first vibration element. 3 The vibrating element 30 vibrates in the X direction.

As shown in FIGS. 15 and 16, the vibrating element 2d includes a first vibrating element 10d, a second vibrating element 20d, and a third vibrating element 30, and has a fixed portion 50d having a square pyramidal trapezoidal shape. , And the substrate 3 are connected.

The third vibrating element 30 includes a third base 43, a third vibrating arm 31 extending from the third base 43, and a fifth driving unit 32 and a sixth driving unit 33 for vibrating the third vibrating arm 31. , Have. In the present embodiment, the third base 43 of the third vibrating element 30 and the third vibrating arm 31 have substantially the same shape as the second base 42d of the second vibrating element 20d and the second vibrating arm 21d, respectively. Have.

The first base portion 41d of the first vibrating element 10d, the second base portion 42d of the second vibrating element 20d, and the third base portion 43 of the third vibrating element 30 are connected in this order toward the plus side in the Z direction. The base is 40d.

The first vibrating arm 11d of the first vibrating element 10d, the second vibrating arm 21d of the second vibrating element 20d, and the third vibrating arm 31 of the third vibrating element 30 are arranged in the Z direction and Y of the base 40d. It extends from one end 40a on the plus side in the direction to the plus side in the Y direction.

Further, on the side surface of the third vibrating arm 31 on the negative side in the X direction, a fifth drive unit 32 in which the second electrode 17d, the piezoelectric film 16d, and the first electrode 15d are laminated in this order from the third vibrating arm 31 side is formed. It is provided. On the side surface of the third vibrating arm 31 on the plus side in the X direction, a sixth drive unit 33 in which the first electrode 15d, the piezoelectric film 16d, and the second electrode 17d are laminated in this order from the third vibrating arm 31 side is provided. ing.

As shown in FIGS. 16 and 17, on the side surface of the second vibrating arm 21d on the negative side in the X direction, the first electrode 15d, the piezoelectric film 16d, and the second electrode 17d are laminated in this order from the second vibrating arm 21d side. A third drive unit 22d is provided. On the side surface of the second vibrating arm 21d on the plus side in the X direction, a fourth drive unit 23d in which the second electrode 17d, the piezoelectric film 16d, and the first electrode 15d are laminated in this order from the second vibrating arm 21d side is provided. ing.

Further, a first drive unit 12d having the same configuration as the fifth drive unit 32 is provided on the side surface of the first vibrating arm 11d on the negative side in the X direction. A second drive unit 13d having the same configuration as the sixth drive unit 33 is provided on the side surface of the first vibrating arm 11d on the plus side in the X direction.

The first electrodes 15d of the first drive unit 12d, the second drive unit 13d, the third drive unit 22d, the fourth drive unit 23d, the fifth drive unit 32, and the sixth drive unit 33 are respectively. , Electrically connected by wiring (not shown). The second electrodes 17d of the first drive unit 12d, the second drive unit 13d, the third drive unit 22d, the fourth drive unit 23d, the fifth drive unit 32, and the sixth drive unit 33 are respectively. , Electrically connected by wiring (not shown).

The first vibrating arm 11d of the first vibrating element 10d and the third vibrating arm 31 of the third vibrating element 30 vibrate in the same phase along the X direction, and the first vibrating arm 11d and the third vibrating arm 31 , The second vibrating arm 21d of the second vibrating element 20d vibrates in opposite phases along the X direction. By vibrating the adjacent vibrating arms in opposite phases in this way, the vibration of the vibrating element 2d is stabilized.

According to the present embodiment, the same effect as that of the first embodiment can be obtained even when the vibrating direction of the vibrating element 2d is the X direction.

Further, according to the present embodiment, since the fixed portion 50d has a square pyramidal trapezoidal shape, the same effect as that of the third embodiment can be obtained.

6. Embodiment 6
Next, the vibration device 1e according to the sixth embodiment will be described with reference to FIGS. 18 to 20. In the following description, the differences from the above-described first embodiment will be mainly described, and the same components as those in the first embodiment are designated by the same reference numerals and duplicated description will be omitted.

The material of the vibration element 2e of the vibration device 1e according to the present embodiment is different from that of the vibration device 1 of the first embodiment. Specifically, the first vibrating arm 11e of the first vibrating element 10e, the first base portion 41e, the fixing portion 50e, the second vibrating arm 21e of the second vibrating element 20e, and the second base portion 42e are piezoelectric. It is made of a material, such as quartz.

As shown in FIGS. 18 and 19, the vibrating element 2e has a first vibrating element 10e and a second vibrating element 20e, and a fixed portion 50e having a square trapezoidal shape and a substrate 3 are connected to each other. Has been done.

The first base portion 41e of the first vibrating element 10e and the second base portion 42e of the second vibrating element 20e are connected in this order toward the plus side in the Z direction to form the base portion 40e.

The first vibrating arm 11e of the first vibrating element 10e and the second vibrating arm 21e of the second vibrating element 20e are aligned in the Z direction and extend from one end 40a on the positive side in the Y direction of the base 40e to the positive side in the Y direction. It is out.

The second electrode 17e is formed on the upper surface and the lower surface of the second vibrating arm 21e, and the first electrode 15e is formed on both the positive side and the negative side in the X direction of the second vibrating arm 21e.

As shown in FIGS. 19 and 20, a first electrode 15e is formed on the upper surface and the lower surface of the first vibrating arm 11e, and a second electrode 15e is formed on both the positive and negative sides of the first vibrating arm 11e in the X direction. The electrode 17e is formed.

The first electrode 15e of the first vibrating arm 11e and the first electrode 15e of the second vibrating arm 21e are electrically connected by wiring (not shown). The second electrode 17e of the first vibrating arm 11e and the second electrode 17e of the second vibrating arm 21e are electrically connected by wiring (not shown).

By forming the first vibrating arm 11e and the second vibrating arm 21e with a crystal, the first vibrating element 10e is vibrated by the first electrode 15e, the second electrode 17e, and the first vibrating arm 11e. Similarly, the second vibrating element 20e can be vibrated by the first electrode 15e, the second electrode 17e, and the second vibrating arm 21e.

The arrangement of the first electrode 15e and the second electrode 17e on the first vibrating arm 11e and the arrangement of the first electrode 15e and the second electrode 17e on the second vibrating arm 21e are opposite to each other. As a result, the first vibrating element 10e and the second vibrating element 20e vibrate in opposite phases to each other, so that the vibration of the vibrating element 2e is stable. In this embodiment, the crystal axes of the crystals constituting the first vibrating arm 11e and the second vibrating arm 21e are selected so that the first vibrating element 10e and the second vibrating element 20e vibrate in the Z direction. However, the crystal axis may be selected so as to vibrate in the X direction.

In this embodiment, quartz is used as the piezoelectric material, but the piezoelectric material may be, for example, ceramics such as AlN, ZnO, and PZT.

According to the present embodiment, the same effect as that of the first embodiment can be obtained even when the crystal is used as the first vibrating arm 11e and the second vibrating arm 21e.

Further, according to the present embodiment, since the fixed portion 50e has a square pyramidal trapezoidal shape, the same effect as that of the third embodiment can be obtained.

The vibration devices 1 to 1e described above can be suitably used as an inertial sensor such as an oscillator, an acceleration sensor, or an angular velocity sensor.

1 to 1e ... vibration device, 2 to 2e ... vibration element, 3 ... substrate, 3h ... top surface of the substrate, 4 ... lid, 6 ... accommodation space, 10 to 10e ... first vibration element, 11, 11d, 11e ... 1st vibrating arm, 12, 12d ... 1st drive unit, 13, 13d ... 2nd drive unit, 15, 15d, 15e ... 1st electrode, 16, 16d ... Piezoelectric film, 17, 17d, 17e ... 2nd Electrodes, 19 ... External electrodes, 20, 20d, 20e ... Second vibrating elements, 21,21d, 21e ... Second vibrating arms, 22, 22d ... Third drive unit, 23, 23d ... Fourth drive unit, 30 ... 3 vibrating element, 31 ... 3rd vibrating arm, 32 ... 5th drive unit, 33 ... 6th drive unit, 40, 40d, 40e ... base, 40a ... one end of the base on the positive side in the Y direction, 41, 41d, 41e ... 1st base, 42, 42d, 42e ... 2nd base, 43 ... 3rd base, 50-50e ... Fixed part, 50h ... Base side connection part of fixed part, 50r ... Board side connection part of fixed part, 55 ... Constriction Part, S1 ... Area of the substrate side connection part of the fixed part, S2 ... Area of the base side connection part of the fixed part, S3 ... Area of the constricted part, L1 ... Center line in the Y direction of the fixed part, L2 ... Y direction of the base Center line.

Claims (9)

A board with a flat surface and
A fixing portion protruding from the substrate in the normal direction of the plane,
The base connected to the fixing part and
A plurality of vibrating arms extending from the base in a direction intersecting the normal direction and arranged side by side in the normal direction are provided.
The fixed portion is included in the outer shape of the base portion in a plan view from the normal direction, and has a smaller area than the base portion.
Vibration device. The fixed portion is arranged so as to be biased to the side opposite to the extending side of the plurality of vibrating arms of the base portion in the plan view.
The vibration device according to claim 1. The fixing portion has a constricted portion between a substrate-side connecting portion in which the substrate and the fixing portion are connected and a base-side connecting portion in which the fixing portion and the base portion are connected.
The vibration device according to claim 1 or 2. In the plan view, when the area of the substrate side connection portion is S1 and the area of the base side connection portion is S2,
S1 ≠ S2
Is,
The vibration device according to any one of claims 1 to 3. The S1 and the S2 are
S1> S2
Satisfy the relationship,
The vibration device according to claim 4. The S1 and the S2 are
S1 <S2
Satisfy the relationship,
The vibration device according to claim 4. The fixed portion has a gradual increase or decrease in cross-sectional area from the substrate-side connection portion to the base-side connection portion in the plan view.
The vibration device according to any one of claims 3 to 6. The substrate, the fixing portion, the base portion, and the vibrating arm are made of silicon.
A piezoelectric film is formed on at least one of the vibrating arms.
The vibration device according to any one of claims 1 to 7. The fixed portion, the base portion, and the vibrating arm are made of quartz.
The vibration device according to any one of claims 1 to 7.

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